package cn.tedu.v3;

import java.io.*;
import java.net.BindException;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.Scanner;

/**
 *  Version3.0  升级   双向链接【客户端与服务器互相说话】
 *
 *  优化空间：代码结构、流没有关闭
 */
public class Server {
    private ServerSocket serverSocket;
    public Server(){
        try {
            serverSocket=new ServerSocket(4545);
        }catch (BindException e){
            System.out.println("端口号重复申请，建议换个端口号");
        }catch (IOException e) {
            System.out.println("申请端口号失败....");
        }
    }
    public void start()  {
        try {
            while(true) {
                System.out.println("-------等待客户端链接------");
                Socket socket = serverSocket.accept();
                String ip = socket.getInetAddress().getHostAddress();
                System.out.println(ip + "客户端链接成功了");
                new Thread(new CS(socket)).start();

            }
        } catch (IOException e) {
            System.out.println("服务器端通讯断开了");
        } finally {
            if(serverSocket!=null&&!serverSocket.isClosed()){
                try {
                    serverSocket.close();
                } catch (IOException e) {
                    System.out.println("服务器关闭失败");
                }
            }

        }

    }
    public static void main(String[] args) {
        new Server().start();
    }

    private class CS implements Runnable{
        private Socket socket;
        private String ip;
        public CS(Socket s){
            this.socket=s;
            ip=socket.getInetAddress().getHostAddress();
        }
        public void run() {
            //BufferedReader br=null;
            PrintWriter pw=null;
            try{
            //2.定义写出
            pw=new PrintWriter(new BufferedWriter(new OutputStreamWriter(socket.getOutputStream(),"UTF8")),true);
            //1.定义读入
            BufferedReader br = new BufferedReader(new InputStreamReader(socket.getInputStream(), "UTF8"));

            //1.1读入功能：存线程中
            new Thread(()->{
                try {
                    String message;
                    while ((message=br.readLine())!=null){
                        System.out.println(ip+"客户端说："+message);
                        //增加写出一句话：读完卡住等待输入
                        System.out.println("服务器请输入：");
                    }
                } catch (IOException e) {
                    System.out.println("客户端读入失败！");
                }

            }).start();
            //2.1 提供写方法：控制台输入
            Scanner input=new Scanner(System.in);//后台卡住
            while (true) {
                System.out.println("服务器请输入：");
                String say=input.nextLine();//得到控制台输入值
                //打印：服务器端说的文本---打印客户端
                pw.println("服务器说："+say);

            }
            }catch (NullPointerException e){
                System.out.println("IO流传入对象，有对象为null，立马核对，建议：查看Try块中对象可能没有对象");
            }catch (UnsupportedEncodingException e){
                System.out.println("客户端或者服务器端：字符集不一致");
            }catch (IOException e) {
                System.out.println("通讯过程中，传输出现错误！");
            }finally {
                /*if (br!=null)
                    try {
                        br.close();
                    } catch (IOException e) {
                        System.out.println("结束通讯：关闭失败！");
                    }*/
                if(socket!=null&&!socket.isClosed()){
                    try {
                        socket.close();
                    } catch (IOException e) {
                        System.out.println("通讯关闭失败~");
                    }
                }
            }
        }
    }
}
